Flora of New Zealand Series

≡Trichothelium alboatrum var. javanicum F.Schill., Hedwigia 67: 279 (1927).

Description : Thallus continuous to sparingly rimose, pale brownish grey to greenish grey, 20–40(–60) μm thick. Perithecia superficial, sometimes slightly attenuated at the base, 0.18–0.3 mm diam. Involucrellum purple-black to black, 40–60 μm thick, with a subapical ring of setae. Setae (50–)80–150(–200) μm long, 15–30 μm thick at base, tapering to apices, uniformly black or with pale tips, occasionally intertwining and coalescing. Asci elongate-cylindrical to elongate-fusiform, 84–100 × 11–13 μm. Ascospores elongate-ellipsoidal to ±fusiform, 3-septate, (18–)22(–26) × 4– 6 μm. Pycnidia very numerous, almost entirely immersed in thallus, 80–100 μm diam. Conidia elongate-ellipsoidal to fusiform, 1.2–1.8 × 0.5 μm.

S: Otago (Trotter's Gorge, Mihiwaka, Swampy Spur). On semi-immersed rocks at edge of stream, on fronds of Hymenophyllum demissum and leaves of Pseudowintera colorata (McCarthy & Johnson 1995). Also known from Christmas I., Indonesia, Hawai'i, Vanuatu, Australia, Lord Howe I., Tasmania and southern South America (Lücking et al. 2001, 2003; McCarthy et al. 2001; McCarthy 2001i: 156, 2001l: 399, 2003c, 2003d). New Zealand records are a significant extension of the range of this species into cool-temperate habitats and the occurrence of a specimen on semi-immersed rocks at Trotter's Gorge is unusual for a genus that is predominantly associated with the leaves of tropical trees, shrubs and ferns.

Palaeotropical

Illustrations : Santesson (1952: 267, fig. 41A); Vězda (1994a: 140, fig. 10); Australasian Lichenological Newsletter 37 (1995: front cover – drawing by P.M. McCarthy); Malcolm & Galloway (1997: 174); Malcolm & Malcolm (2000: 109; 2001: 37).

Trichothelium javanicum is characterised by: the saxicolous habit (aquatic rocks); its large perithecia and the 3-septate spores, 18–26 × 4–6 μm; very numerous pycnidia, almost entirely immersed in thallus, 80–100 μm diam.; and elongate-ellipsoidal to fusiform conidia, 1.2–1.8 × 0.5 μm.